8991765 has 24 divisors (see below), whose sum is σ = 15676128. Its totient is φ = 4767840.

The previous prime is 8991761. The next prime is 8991779. The reversal of 8991765 is 5671998.

It is not a de Polignac number, because 8991765 - 2² = 8991761 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 8991765.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8991761) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9022 + ... + 9968.

It is an arithmetic number, because the mean of its divisors is an integer number (653172).

Almost surely, 2^8991765 is an apocalyptic number.

It is an amenable number.

8991765 is a deficient number, since it is larger than the sum of its proper divisors (6684363).

8991765 is a wasteful number, since it uses less digits than its factorization.

8991765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1169 (or 1166 counting only the distinct ones).

The product of its digits is 136080, while the sum is 45.

The square root of 8991765 is about 2998.6271858969. The cubic root of 8991765 is about 207.9449203888.

The spelling of 8991765 in words is "eight million, nine hundred ninety-one thousand, seven hundred sixty-five".